My experts cant agree...correct spark plug?

[simmonatural]

I have a 92 Johnson V6 150 60 degree motor...
owners manual: ql77jc4, optional ql16v for sustained high speed operation
johnson master mechanic: ql78yc
other master marine mechanic: ql77jc4

I have seen the "chart," so have my experts, but one says that according to the service bulletin, the chart is incorrect for my year motor.

Apparently there was a service bulletin that called for the ql78yc in 150 v6 60 degree motors,
but the question is for what year span was that change recommended?
Getting told it was 94 and newer on one side of the argument.
Just want to run the right plugs...
Thanks for the help!

 

[boobie]

Re: My experts cant agree...correct spark plug?

I'd have to say go with the QL78YC in that mtr.

 

[simmonatural]

Re: My experts cant agree...correct spark plug?

I'd have to say go with the QL78YC in that mtr.

Thanks, It seemed to idle better when the 78s were in before anyway,
I hate to question my trusted and talented mechanics, so thanks for the clarity.

 

[Haffiman]

Re: My experts cant agree...correct spark plug?

QL78YC for optimal idling and low speed operations like trolling etc. As mentioned, QL16V if high speed/rpm and extended plug life is priority.

 

[seahorse5]

Re: My experts cant agree...correct spark plug?

Back in about 1995, OMC changed the recommended sparkplug to QL78YC. On a lot of older motors you will find improved running characteristics at low speeds with the new extended nose plug gapped to .030"

Here is the official factory sparkplug chart

http://continuouswave.com/whaler/reference/BRP/SparkPlugChart2008.pdf

 

[simmonatural]

Re: My experts cant agree...correct spark plug?

Thanks you all for your replies, this site is a great resource.
Now, on to the VRO overhaul.

 

[seahorse5]

Re: My experts cant agree...correct spark plug?

This link has been around for a lot of years and is the only one that really explains how the "VRO" works

http://continuouswave.com/whaler/reference/VRO.html

 

[simmonatural]

Re: My experts cant agree...correct spark plug?

yes, thank you sea horse, I just found that article and had a good read.

I believe i can service my inlet housing assy, as there is a fuel/air leak there, I believe this is my source of "foamy" gas, and high speed hiccups/stalling. i will also replace my vacuum o ring if possible.

Thanks again for the help, and any other related tips/tricks are very welcome.